1. Field of the Invention
The present invention relates to a fan unit.
2. Description of the Related Art
For example, in an inverter apparatus disclosed in Japanese Unexamined Patent Application Publication No. 2008-135422 that was published Jun. 12, 2008, heating elements, such as an insulate gate bipolar transistor (IGBT) that generates a high heat, a capacitor, and a reactor, are incorporated in a housing. A heat sink is used to cool these elements, and a cooling fan for forced air cooling is mounted at one end of the housing.
When the capacity of the inverter apparatus is small and only one cooling fan will do, a fan case is attached to the housing by engagement of projections without using any fixing screw. In contrast, when the capacity of the inverter apparatus is large and a plurality of cooling fans are used, the fan case is firmly attached to the housing with fixing screws.